Painting Gurus!! Tips on setting up my HVLP guns?!?!

diesel450

"Fast with a past"
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Picked up a set of HVLP guns from TCP-global and I'm trying to figure out how to get them set up right. I got pretty good with my old conventional gun so I'm sure that once i get the hang of these I should get decent results. I'm currently spraying epoxy primer which will get a single stage urethane top coat. any tips on setting up to get these finishes to lay nice and flat?


I'm using the recommended 4-1-1 mix ratio on the urethane and am reducing the primer the max. 10%.


I seem to be getting a lot of spitting and splatter and probably too much material coming out. I was going to reduce that a bit and just experiment but some base line guide lines would be great.


Thanks in advance for any help!
 
I've got a pressure gauge on the gun and have followed the manufacturer specs of 29psi at the inlet for 10psi at the cap. I am using the 1.4 tip gun which also falls in spec with what is recommended. Not sure what you mean by needle set up? do I need to do something with the needle that is under the cap?
 
ok cool.
by needle set up i mean the size, which in this case your using 1.4
im not sure what primer you are using exactly, but sounds like the needle might be to small, all the primers i have shot ive usualy used a 1.8 or 1.9, and my 1.4 and smaller guns for paint and clear, but then again, you primer is probably totally different and companys keep changing this stuff up.
try reducing a little bit more, maybe going about 33psi and mess with the flow adjustment a bit.
 
Geez, what took you so long? :D


Thanks, sounds like my thinking was on the right track. I do have a 1.8 gun as well but the tech sheet called for the smaller. could try the other just to see.


Thanks!
 
yeah i would try the other gun for sure dude, im sure youll figure it out, alot of this is trial and error
 
a good filter on there is gold. drain your tank often;youll find theres a LOT of water buildup.

just two tips.

agreed with hurley... a lot of this is trial and error. try painting random crap you dont care about (like friends bicycle frames ;)) and just see what each setting does. its a lot about feel. also about HOW you paint. what works for you might not work for another person, and vice versa.
 
Well, let me see if I can give you some pointers on getting it to shoot somewhere close to right for you.


There should be three adjustments on the gun, two of them will be on the back of the gun near its top and one will either be at the bottom, like an Iwata, or on the gun's side, like a Sata. Here is what you need to do with them. First its a very good thing that you got a gage at the gun, you need that. Turn your air pressure in the line up to the gun up all the way, to 100 pounds or so, and leave it there. Now turn the pressure at the gun up to about 30 or 40 pounds. Next hold the gun in your and and pull back the trigger to blow air, but no paint. Find that odd adjusting knob, the one that is either on the bottom or the side, and close it down and you'll see the pressure at your gage go way up, now open the adjuster on the gun slowly and watch the pressure begin to drop. Keep opening that knob until the pressure quits dropping, and then quit. Now move back down to the pressure regulator at your gage and adjust it for your 29 pounds or whatever it is your gun manufacturer recommends.


OK, next adjustment. Now you move to you trigger pull. This will be the adjuster on the back, probably the lower of the two. This one will effect trigger pull. I should have told you to do this first, but what you need to do is screw this adjustment all the way in - not too tight, just seat the needle. Now while counting turns, while pulling the trigger, start unscrewing the adjusting knob until the triger has moved all the way back. It should take about 4 turns, maybe 5. Whatever it is screw the adjuster all the way back in and then back it out half the number of turns to full trigger pull. This is just a safe starting point, about half trigger pull. You can open it up to three quarters way if you want but I do not suggest that you open it up all the way at first. As you paint open this adjustment up a little bit at a time until you get a paint flow that you feel comfortable with with the speed you like to move.


Now the final adjustment, which is the fan pattern. Tape a piece of paper up to the wall and hold your gun back from it about 9" or so and give the trigger a very quick blip, just pop it open and shut. It will blow out a pattern of paint on your paper and what you want to do is adjust that knob until that pattern is first of the height you want and then sort of vertically cigar shaped with even paint distribution all across that pattern.


So now you've got it pretty well adjusted and you can make any subtle changes you need to as you shoot your first coat. Set up like I recommended it will probably shoot a little bit dry, and if that's the case open up the trigger pull a bit. If you're getting runs open up the air a bit (at the handle, not at that cap pressure adjusting knob - leave it alone).


There. That help any?


Kong.
 
Kong! That is exactly what I needed to know! Thanks! I can't wait to give it a try.

I do understand that everyone is different and all the paint acts differently etc. just need a baseline to go from !
 
Ive been a painter since right out of high school and the few tips I have is turn the pressure up 2 or 3 from what they say you should have, and reduce it a bit more than your supposed to also if you want things to lay out and all blend in well. You can use a bit of a blend thinner in your clear or normal paint which will make it easier to run but just being a bit more careful will help it in the end.

Of course, all of this depends on what type of gun you have...If its a cheap gun, laying paint/clear out is much harder to lay out...
 
Also, another thing on what kong said, the pattern on the paper is a good idea, if your finding one end, as in the bottom or top is heavier than the other, you need to check what reducer you are using...And slow it down...With colors with a lot of metal flake it will show a line if you have one end that is setting down heavier than the other..Although, on bikes your not working on big areas so this pretty much is useless haha...Im used to painting vans, etc all day long..
 
Are you saying to put some of the base coat in with the clear? not quite, um, clear on that. :eek:


They are cheap guns, no doubt, but I got to where I could lay the clear FLAT with my $60 conventional gun. I'm told these HVLP's will help improve the results even more. But I don't know. I did a bit of research and these TCp guns are supposed to emulate more expensive gear, similar atomization etc. but again, I don't really know.


Thanks for the tips!
 
Old car hoods work great for setting up the gun for proper spray pattern. One thing I hope some of the painters out there can answer is the turbine vs. compressor driven HVLP systems. I have an older Graco unit that works great and runs off of dedicated turbine in the unit. The air line the goes to the gun is about the size of a garden hose, no compressor required. Is there advantages/disadvantage to either set up? I still use standard cups guns also with my compressor and never understood the advantage of a compressor style HVLP (which is what most people seem to have ??? )
 
I agree that raising the inlet air pressure (at the handle adjuster/gage) is often a good idea. On reducers - and this is very important - they are graded by the temperature range in which they are to be used. What you find in the real world is that there are (depending on the manufacturer) 3 speeds of the stuff, slow, medium, and fast. You want to follow the manufacturer's recommendation as to which one to use at what temperatures - but at the same time keep this old monkey's advice in mind, always use the slowest reducer you can get away with.


On the hint from Midcoastcustoms - dam right, go get an old door or trunk lid or something to use as a test panel. When in doubt do a test panel. I only do a few paint jobs a year and only do motorcycles myself. I have a couple of old side panels off a riding lawn mower that I use, they are about a foot and a half by two feet that work great. I use them any time I try a new material out or plan to mix materials that I'm not familiar with. I also use them to do example pieces for customers to make sure we're of the same mind about what their job is going to look like or what the finished color will really look like out in the sun. The very worst words a custom painter can ever hear from a customer are 'Oh no, that's not what I had in mind at all", and believe me, it happens. Test panels are invaluable.


Kong
 
Good advice. I bought the fast reducer too, recommended for 60-75 degrees. I will find some test panels to work on.
 
I agree with Kong...

No I wasnt saying put the base in with the clear. I was saying if you're having problems with clear laying out to get a 'blend thinner' or a reducer specially made for clear and try adding a cap or two full into the clear. But with the fact that your working with such small area's like bike stuff, getting things to lay flat are not as hard..Its more of just a fact of dusting it until its shiny more than doing say a big van like I do every day of my damn life and trying to get the clear to lay flat on something like that. The biggest thing with painting, as far as Im concerned, and how I learned all my things, is taking advice (like your taking from us right now) from painters, and just tweaking it to what your looking for. Meaning, I only could use so much advice before I just started trying things and seeing if it worked.

The max inlet on my clear gun is 30 but I feel like Id have to be insane to run it that high. Im at 22PSI and the thing sprays glass flat...

So basically what Im saying is like someone said on here...Take an old hood, or something tin, and just start spraying it and adjusting until you get it how you want it..
 
Salvaged a truck hood and cut it into panels to try some stuff. I got the primer laying pretty hood. I'll try lowering the pressure and see what happens.
 
Yeah, pressure and paint flow are things that get real personal, and of course every gun is a little different too. You get real attached to your guns. I shoot clear with an Iwata LPH300LV. The manufacturer's recommendation for handle pressure for it is (I think) 19 pounds, but I run it closer to 22 most of the time, but then I also run it with a compressed pattern but less trigger pull than almost anyone else you will ever talk to - just because it suites my style. Like the man said, take advice to get it close and then fiddle with it, you'll find the sweet spot for yourself quicker than you might imagine.


Those TCP guns will treat you OK, you'll just end up doing more sanding than otherwise. Keep the guns real clean and go to extremes to keep your air clean, dry, and cool - I mean extremes. After a while you'll be able to lay down that clear like the breath of an angel, but then a bug will take a hike through it or a meteorite will land in it, one way or another, there you are cutting and buffing.


One thing that I've already mentioned that I really can not emphasize too much - find and read the tech sheets for the paints you plan to use. They are an invaluable aid in getting it right.
 
Thanks,

I can already see that advice can take you only so far. I will be playing with this for a while.

I do have the tech sheets and keep them close at hand.

One question; One paint recommends not more than 4 mils of thickness when wet. how the hell do you measure that?!?!?!
 
I cant say Ive heard of that much before...But if it were me personally, 4 mils would sound like four wet coats...If it were me, Id just go three coats...First one light, just a cover...second one heavy...and third one a dusting but a strong dusting..Especially if its a color with any pearls..
 
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